The majestic spire of the Empire State Building is familiar to many people throughout the world, but not
many know that the original purpose of the mast was to serve as a landing spot for dirigibles, also known
as blimps. Read the excerpt from “The Mooring Mast” and answer the questions that follow.
THE MOORING MAST
by Marcia Amidon Lüsted
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When the Empire State Building was conceived, it
was planned as the world’s tallest building, taller
even than the new Chrysler Building that was being
constructed at Forty-second Street and Lexington
Avenue in New York. At seventy-seven stories, it
was the tallest building before the Empire State
began construction, and Al Smith* was determined
to outstrip it in height.
The architect building the Chrysler Building,
however, had a trick up his sleeve. He secretly
constructed a 185-foot spire inside the building,
and then shocked the public and the media by
hoisting it up to the top of the Chrysler Building,
bringing it to a height of 1,046 feet, 46 feet taller
than the originally announced height of the Empire
State Building.
Al Smith realized that he was close to losing The top of the Empire State Building
the title of world’s tallest building, and on
December 11, 1929, he announced that the Empire State would now reach the height
of 1,250 feet. He would add a top or a hat to the building that would be even more
distinctive than any other building in the city. John Tauranac describes the plan:
[The top of the Empire State Building] would be more than ornamental,
more than a spire or dome or a pyramid put there to add a desired few
feet to the height of the building or to mask something as mundane as a
water tank. Their top, they said, would serve a higher calling. The Empire
State Building would be equipped for an age of transportation that was
then only the dream of aviation pioneers.
* Al Smith — four-term governor of New York who headed efforts to construct the Empire State Building after his years in office
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This dream of the aviation pioneers was travel by dirigible, or zeppelin, and the
Empire State Building was going to have a mooring mast at its top for docking these
new airships, which would accommodate passengers on already existing transatlantic
routes and new routes that were yet to come.
THE AGE OF DIRIGIBLES
By the 1920s, dirigibles were being hailed as the
transportation of the future. Also known today as
blimps, dirigibles were actually enormous steelframed balloons, with envelopes of cotton fabric
filled with hydrogen and helium to make them
lighter than air. Unlike a balloon, a dirigible
could be maneuvered by the use of propellers
and rudders, and passengers could ride in the
gondola, or enclosed compartment, under the
balloon.
Dirigibles had a top speed of eighty miles
per hour, and they could cruise at seventy miles
per hour for thousands of miles without needing
refueling. Some were as long as one thousand
feet, the same length as four blocks in New
York City. The one obstacle to their expanded A simulated image of a dirigible docking
use in New York City was the lack of a suitable at the mooring mast
landing area. Al Smith saw an opportunity for
his Empire State Building: A mooring mast added to the top of the building would
allow dirigibles to anchor there for several hours for refueling or service, and to let
passengers off and on. Dirigibles were docked by means of an electric winch, which
hauled in a line from the front of the ship and then tied it to a mast. The body of
the dirigible could swing in the breeze, and yet passengers could safely get on and
off the dirigible by walking down a gangplank to an open observation platform.
The architects and engineers of the Empire State Building consulted with experts,
taking tours of the equipment and mooring operations at the U.S. Naval Air Station in
Lakehurst, New Jersey. The navy was the leader in the research and development of
dirigibles in the United States. The navy even offered its dirigible, the Los Angeles, to
be used in testing the mast. The architects also met with the president of a recently
formed airship transport company that planned to offer dirigible service across the
Pacific Ocean.
When asked about the mooring mast, Al Smith commented:
[It’s] on the level, all right. No kidding. We’re working on the thing now.
One set of engineers here in New York is trying to dope out a practical,
workable arrangement and the Government people in Washington are
figuring on some safe way of mooring airships to this mast.
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DESIGNING THE MAST
The architects could not simply drop a mooring mast on top of the Empire State
Building’s flat roof. A thousand-foot dirigible moored at the top of the building,
held by a single cable tether, would add stress to the building’s frame. The stress of
the dirigible’s load and the wind pressure would have to be transmitted all the way
to the building’s foundation, which was nearly eleven hundred feet below. The steel
frame of the Empire State Building would have to be modified and strengthened to
accommodate this new situation. Over sixty thousand dollars’ worth of modifications
had to be made to the building’s framework.
Rather than building a utilitarian mast without any ornamentation, the architects
designed a shiny glass and chrome-nickel stainless steel tower that would be
illuminated from inside, with a stepped-back design that imitated the overall shape
of the building itself. The rocket-shaped mast would have four wings at its corners, of
shiny aluminum, and would rise to a conical roof that would house the mooring arm.
The winches and control machinery for the dirigible mooring would be housed in the
base of the shaft itself, which also housed elevators and stairs to bring passengers
down to the eighty-sixth floor, where baggage and ticket areas would be located.
The building would now be 102 floors, with a glassed-in observation area on the
101st floor and an open observation platform on the 102nd floor. This observation
area was to double as the boarding area for dirigible passengers.
Once the architects had designed the mooring mast and made changes to the
existing plans for the building’s skeleton, construction proceeded as planned. When
the building had been framed to the 85th floor, the roof had to be completed before
the framing for the mooring mast could take place. The mast also had a skeleton
of steel and was clad in stainless steel with glass windows. Two months after the
workers celebrated framing the entire building, they were back to raise an American
flag again—this time at the top of the frame for the mooring mast.
THE FATE OF THE MAST
The mooring mast of the Empire State Building was destined to never fulfill its
purpose, for reasons that should have been apparent before it was ever constructed.
The greatest reason was one of safety: Most dirigibles from outside of the United
States used hydrogen rather than helium, and hydrogen is highly flammable. When
the German dirigible Hindenburg was destroyed by fire in Lakehurst, New Jersey,
on May 6, 1937, the owners of the Empire State Building realized how much worse
that accident could have been if it had taken place above a densely populated area
such as downtown New York.
The greatest obstacle to the successful use of the mooring mast was nature itself.
The winds on top of the building were constantly shifting due to violent air currents.
Even if the dirigible were tethered to the mooring mast, the back of the ship would
swivel around and around the mooring mast. Dirigibles moored in open landing fields
could be weighted down in the back with lead weights, but using these at the Empire
State Building, where they would be dangling high above pedestrians on the street,
was neither practical nor safe.
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The other practical reason why dirigibles could not moor at the Empire State
Building was an existing law against airships flying too low over urban areas. This
law would make it illegal for a ship to ever tie up to the building or even approach the
area, although two dirigibles did attempt to reach the building before the entire idea
was dropped. In December 1930, the U.S. Navy dirigible Los Angeles approached
the mooring mast but could not get close enough to tie up because of forceful
winds. Fearing that the wind would blow the dirigible onto the sharp spires of other
buildings in the area, which would puncture the dirigible’s shell, the captain could
not even take his hands off the control levers.
Two weeks later, another dirigible, the Goodyear blimp Columbia, attempted a
publicity stunt where it would tie up and deliver a bundle of newspapers to the
Empire State Building. Because the complete dirigible mooring equipment had never
been installed, a worker atop the mooring mast would have to catch the bundle of
papers on a rope dangling from the blimp. The papers were delivered in this fashion,
but after this stunt the idea of using the mooring mast was shelved. In February
1931, Irving Clavan of the building’s architectural office said, “The as yet unsolved
problems of mooring air ships to a fixed mast at such a height made it desirable to
postpone to a later date the final installation of the landing gear.”
By the late 1930s, the idea of using the mooring mast for dirigibles and their
passengers had quietly disappeared. Dirigibles, instead of becoming the transportation
of the future, had given way to airplanes. The rooms in the Empire State Building that
had been set aside for the ticketing and baggage of dirigible passengers were made
over into the world’s highest soda fountain and tea garden for use by the sightseers
who flocked to the observation decks. The highest open observation deck, intended
for disembarking passengers, has never been open to the public.
“The Mooring Mast” by Marcia Amidon Lüsted, from The Empire State Building. Copyright © 2004 by Gale, a part of Cengage
Learning, Inc. Reprinted by permission. Photograph 1 © Jeff Albertson/CORBIS. Photograph 2 © Bettmann/CORBIS.